Drop zone: On a visit to Ethiopia, mechanical engineer Peter Frykman saw how people went hungry because of a lack of affordable irrigation equipment for their fields, so he designed an inexpensive drip irrigation system. Only 1 to 2% of clean technology investments is directed to water work, primarily because of the complexity of water rights and regulations. Frykman hopes to begin field testing in India (and also the U.S.) and eventually scale up for much greater deployment. (San Francisco Chronicle)